The present invention relates to a flashlight and more particularly pertains to a flashlight with battery cartridge assembly.
Flashlights of varying construction are known in the art. A conventional flashlight generally comprises a light source such as a light emitting diode, one or more batteries as power source, a switch controlling the on/off status of the light source, contacts making electrical connection of the light source, the battery or batteries and the switch, thereby completing the circuit, and a case which houses the components of the flashlight and is typically in tubular shape serving as a handle for the flashlight. In more complicated designs of available flashlights, a battery cartridge for holding the battery or batteries may be installed to better position the battery or batteries. FIGS. 1 and 2 show the construction and the circuit of a typical aluminum alloy flashlight with rear push button on/off switch. The switch 10 is typically configured as an end cap 20 at the rear of the flashlight so that it may be removable for replacing the battery or batteries 30 in the battery cartridge 60. To complete the circuit, the inner wall of the case 40 is used as an electro-contact, with one end of the case 40 connected electrically to the light source 50 and the other end of the case 40 connected electrically to the switch 10. More specifically, the case 40 is connected to the switch 10 by coupling the threads on one end of the case 40 to the corresponding threads on the end cap 20 and the threads on the end cap 20 are electrically connected to the switch 10. However, in order to enhance the hardness of the case and to improve its aesthetic value, the case 40 of a typical aluminum alloy flashlight usually has to undergo an anodizing process. After the anodizing process, the surface, including the threads of the case 40 becomes electrically non-conductive. Therefore, in order to complete the circuit, it is necessary for the inner wall and the threads of the case 40 to undergo another machining process so as to remove the anodized layer and to reveal the electrically conductive aluminum underneath. The drawback of such construction is that it involves higher manufacturing costs and requires more time and higher level of technical and material investment. It also has higher dimensional variance. During the manufacturing process, it is also not uncommon for the end cap 20 to be fastened to the case 40 with the cartridge 60 being missed to be inserted into the case 40, and this drawback affects product quality and to prevent this, more resources are to be invested on better quality control. Further, when the end cap 20 is removed, the battery cartridge 60 and/or the end cap 20 may be easily lost rendering the flashlight useless.